State profile · Above median Poor share

Iowa bridge safety

Condition ratings, load ratings, and Poor-condition data for every public highway bridge in Iowa, based on the FHWA National Bridge Inventory.

20,753
Public bridges
36.5%
Good condition
20.0%
Poor condition

Data updated May 2026

Total Bridges

20,753

Public highway bridges in Iowa

Good Condition

36.5%

7,582 bridges rated 7-9

-13.5pp vs 50% benchmark

Poor Condition

20.0%

4,153 bridges whose lowest applicable component is rated 0-4

13.0pp vs national avg 7.0%

Iowa vs national bridge condition

Iowa - Good condition share 36.5%
National avg

Share of bridges rated 7-9 on the FHWA 0-9 scale (deck, superstructure, substructure all good).

Iowa - Poor-condition share 66.7%
National avg

Lower is better. Bar maxes at 30% (worst-state ceiling). National average sits at 7.0%.

Condition Distribution

Iowa38.5%40.4%21.1%GoodFairPoor
Bridge inventory deck-condition mix - Iowa (FHWA NBI)

Counties (99)

Adair 208 Adams 147 Allamakee 170 Appanoose 159 Audubon 161 Benton 327 Black Hawk 411 Boone 119 Bremer 220 Buchanan 281 Buena Vista 140 Butler 261 Calhoun 171 Carroll 223 Cass 237 Cedar 265 Cerro Gordo 210 Cherokee 223 Chickasaw 268 Clarke 150 Clay 138 Clayton 214 Clinton 325 Crawford 242 Dallas 154 Davis 156 Decatur 178 Delaware 254 Des Moines 156 Dickinson 73 Dubuque 304 Emmet 70 Fayette 288 Floyd 195 Franklin 214 Fremont 133 Greene 150 Grundy 270 Guthrie 236 Hamilton 134 Hancock 128 Hardin 211 Harrison 162 Henry 144 Howard 193 Humboldt 70 Ida 164 Iowa 189 Jackson 209 Jasper 321 Jefferson 142 Johnson 317 Jones 215 Keokuk 152 Kossuth 256 Lee 185 Linn 428 Louisa 134 Lucas 186 Lyon 241 Madison 221 Mahaska 219 Marion 204 Marshall 283 Mills 170 Mitchell 160 Monona 125 Monroe 126 Montgomery 184 Muscatine 127 O'Brien 229 Osceola 176 Page 185 Palo Alto 114 Plymouth 407 Pocahontas 186 Polk 415 Pottawattamie 469 Poweshiek 221 Ringgold 206 Sac 188 Scott 212 Shelby 194 Sioux 429 Story 262 Tama 307 Taylor 220 Union 153 Van Buren 142 Wapello 160 Warren 231 Washington 203 Wayne 163 Webster 179 Winnebago 48 Winneshiek 317 Woodbury 379 Worth 89 Wright 168

Iowa vs nearby ranks

Adjacent states by Poor-condition share (lower share = better)

States are ranked by the share of bridges whose lowest applicable component rating is 4 or below. This describes recorded condition; it does not measure funding effectiveness or live crossing safety. States here sit immediately above and below Iowa on the same metric.

WV

West Virginia

16.02% top marginal rate
Structure
Progressive
Burden @ $100K
$7,679

SD

South Dakota

16.24% top marginal rate
Structure
Progressive
Burden @ $100K
$5,905
Selected

IA

Iowa

20.01% top marginal rate
Structure
Progressive
Burden @ $100K
$20,753

VI

Virgin Islands

29.17% top marginal rate
Structure
Progressive
Burden @ $100K
$24

Bridges Needing Most Attention in Iowa

Six lowest-condition bridges in Iowa, ranked by the portal's composite display score. Inspection intervals are risk-based under current NBIS rules.

270TH STREET

Poor

Over: ROSE BRANCH

071343401, Adams, IA

Built 1976 Load: 2.7 t ADT: 79

LOCAL

Poor

Over: CREEK

078342601, Audubon, IA

Built 1935 Load: 2.7 t ADT: 21

KLINE RD

Poor

Over: MUD CREEK

87-12-15-02-10, Black Hawk, IA

Built 1948 Load: 2.7 t ADT: 11

LOCAL - 700TH

Poor

Over: TRIB TROUBLESOME CREEK

077351402, Cass, IA

Built 1983 Load: 2.7 t ADT: 11

LOCAL - DAYTONA

Poor

Over: BUCK CREEK

077361903, Cass, IA

Built 1980 Load: 2.7 t ADT: 35

100TH ST.

Poor

Over: UNION CREEK

083E20101, Clinton, IA

Built 1900 Load: 2.7 t ADT: 78

All Bridges in Iowa

FM

Fair

Over: DD JT 22

094342001, Palo Alto, IA

Built 1975 Load: 33.0 t ADT: 350

LOCAL

Fair

Over: DRAINAGE DDJT22

094342004, Palo Alto, IA

Built 1975 Load: 33.0 t ADT: 30

FM

Fair

Over: DD 80

095310601, Palo Alto, IA

Built 1975 Load: 33.0 t ADT: 133

FM

Fair

Over: CYLINDER CREEK

095320103, Palo Alto, IA

Built 1975 Load: 33.0 t ADT: 131

LOCAL RD

Fair

Over: SMALL

095322302, Palo Alto, IA

Built 1979 Load: 33.0 t ADT: 21

LOCAL

Fair

Over: SILVER CREEK

095342308, Palo Alto, IA

Built 1978 Load: 33.0 t ADT: 50

FM

Fair

Over: DD

096321502, Palo Alto, IA

Built 1973 Load: 33.0 t ADT: 40

FM

Fair

Over: DD

096322202, Palo Alto, IA

Built 1977 Load: 33.0 t ADT: 45

FM K-49

Fair

Over: MUDDY CREEK

090451502, Plymouth, IA

Built 1974 Load: 33.0 t ADT: 509

FM

Fair

Over: SMALL

093472302, Plymouth, IA

Built 1978 Load: 33.0 t ADT: 688

LOCAL RD

Fair

Over: DD #29

090343502, Pocahontas, IA

Built 1979 Load: 33.0 t ADT: 26

LOCAL

Fair

Over: N LIZARD CREEK DD#77

091311601, Pocahontas, IA

Built 1982 Load: 33.0 t ADT: 11

LOCAL

Fair

Over: DD #53 LIZARD CK

091320902, Pocahontas, IA

Built 1977 Load: 33.0 t ADT: 50

LOCAL

Fair

Over: N LIZARD CREEK

093330402, Pocahontas, IA

Built 1977 Load: 33.0 t ADT: 5

LOCAL

Fair

Over: N LIZARD CREEK

093330602, Pocahontas, IA

Built 1977 Load: 33.0 t ADT: 50

LOCAL

Fair

Over: N LIZARD CREEK

093330802, Pocahontas, IA

Built 1977 Load: 33.0 t ADT: 11

LOCAL

Fair

Over: PILOT CREEK

093331201, Pocahontas, IA

Built 1976 Load: 33.0 t ADT: 40

INDUSTRAIL CIR

Fair

Over: CREEK

000000000, Polk, IA

Built 1998 Load: 33.0 t ADT: 1,138

LOCAL

Fair

Over: SMALL STREAM

086372501, Sac, IA

Built 1971 Load: 33.0 t ADT: 20

FM

Fair

Over: SMALL

087353301, Sac, IA

Built 1979 Load: 33.0 t ADT: 71

FM

Fair

Over: SMALL

088370504, Sac, IA

Built 1978 Load: 33.0 t ADT: 30

FM

Fair

Over: SMALL STREAM

078370305, Shelby, IA

Built 1957 Load: 33.0 t ADT: 240

LOCAL ROAD

Fair

Over: SOUTH FORK LONG CREEK

075070901, Washington, IA

Built 1965 Load: 33.0 t ADT: 131

LOCAL ROAD

Fair

Over: CLEMONS CREEK

075080902, Washington, IA

Built 1969 Load: 33.0 t ADT: 26

FM

Fair

Over: DD NO 5

087302301, Webster, IA

Built 1974 Load: 33.0 t ADT: 230

FM

Fair

Over: DRAINAGE DITCH NO 96

088292702, Webster, IA

Built 1976 Load: 33.0 t ADT: 429

FM

Fair

Over: DD NO 69

088301101, Webster, IA

Built 1974 Load: 33.0 t ADT: 339

FM

Fair

Over: DRAINAGE

089271802, Webster, IA

Built 1977 Load: 33.0 t ADT: 359

FM

Fair

Over: DRAINAGE DITCH NO 4

089272301, Webster, IA

Built 1975 Load: 33.0 t ADT: 878

FM

Fair

Over: DRAINAGE DITCH NO 4

089272301, Webster, IA

Built 1975 Load: 33.0 t ADT: 878

FM

Fair

Over: DD NO 57

089281201, Webster, IA

Built 1974 Load: 33.0 t ADT: 828

FM

Fair

Over: DRAINAGE DITCH NO.4

090272903, Webster, IA

Built 1987 Load: 33.0 t ADT: 26

FM

Fair

Over: BADGER CREEK

090280904, Webster, IA

Built 1977 Load: 33.0 t ADT: 1,257

FM

Fair

Over: DRAINAGE DITCH NO 3

090302801, Webster, IA

Built 1976 Load: 33.0 t ADT: 489

CORP.LINE RD

Fair

Over: WEST NISHNABOTNA RIVER

082361701, Carroll, IA

Built 1980 Load: 33.1 t ADT: 289

FM

Fair

Over: BRANCH TURKEY RIVER

097112101, Chickasaw, IA

Built 1992 Load: 33.1 t ADT: 216

FM

Fair

Over: WEST CREEK

073262506, Clarke, IA

Built 1971 Load: 33.1 t ADT: 428

280TH AVE

Fair

Over: DEEP CREEK

083E43004, Clinton, IA

Built 1975 Load: 33.1 t ADT: 51

EB US 30

Fair

Over: SILVER CK & UP RR

0.7 MI. E OF W JCT US 61, Clinton, IA

Built 1970 Load: 33.1 t ADT: 8,550

FM

Fair

Over: GRAND RIVER

070272702, Decatur, IA

Built 1959 Load: 33.1 t ADT: 89

LOCAL

Fair

Over: STREAM

081330702, Guthrie, IA

Built 1995 Load: 33.1 t ADT: 29

FM

Fair

Over: COPPER CREEK

084E52802, Jackson, IA

Built 1974 Load: 33.1 t ADT: 1,070

SW 470TH ST

Fair

Over: STREAM

078070403, Johnson, IA

Built 1973 Load: 33.1 t ADT: 30

LOCAL RD

Fair

Over: MUD CREEK

100472403, Lyon, IA

Built 1979 Load: 33.1 t ADT: 50

FM

Fair

Over: BLOOD RUN CREEK

100482204, Lyon, IA

Built 1971 Load: 33.1 t ADT: 350

FM

Fair

Over: LITTLE OCHEYEDAN RIVER

098400901, Osceola, IA

Built 1977 Load: 33.1 t ADT: 698

FM

Fair

Over: OCHEYEDON RIVER

099401603, Osceola, IA

Built 1976 Load: 33.1 t ADT: 828

LOCAL

Fair

Over: WEST BRANCH IOWA RIVER

093241301, Wright, IA

Built 1968 Load: 33.1 t ADT: 51

LOCAL

Fair

Over: BOONE RIVER

093261602, Wright, IA

Built 1968 Load: 33.1 t ADT: 31

EASTMAN RD

Fair

Over: TRIB TO MILLER CREEK

87-12-08-01-10, Black Hawk, IA

Built 1983 Load: 33.2 t ADT: 11

Showing 7,201-7,250 of 20,753 bridges

Related

All states → | National rankings → | Understanding conditions → | Retired SD term explained →
Data sourced from the FHWA National Bridge Inventory (NBI), latest released cycle. See our methodology for details. Retrieved and formatted by PlainBridges.

Disclaimer: This information is provided for informational purposes only and does not constitute professional advice. Data is sourced from the FHWA National Bridge Inventory (NBI). Poor condition is an inspection-record category, not a closure or unsafe-to-cross designation. Consult the bridge owner for current status.

Understanding Bridge Conditions

How FHWA rates bridge condition on a 0-9 scale.

Check Your Daily Bridges

How to look up bridge condition data for bridges on your route.

Read our methodology — how this data is sourced, computed, and verified.

Every figure on PlainBridge is rendered directly from federal source data, no number is typed in by an editor. This page draws directly on federal source data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.